CN111497550A - Automobile temperature control device and control method thereof - Google Patents

Abstract

The invention provides an automobile temperature control device and a control method thereof, wherein the method comprises the following steps: s1, monitoring and acquiring a first actual temperature value on the surface of the passenger compartment evaporator, a battery pack temperature value of the battery cooling system, a target temperature value on the surface of the passenger compartment evaporator and a target temperature value of the battery pack in real time; s2, judging whether the passenger compartment side has a refrigeration demand according to the first actual temperature value and the target temperature value of the passenger compartment evaporator surface and judging whether the battery side has the refrigeration demand according to the battery pack temperature value and the battery pack target temperature value; s3, determining the rotation speed of the compressor according to the judgment result of the step S2 and adjusting the opening degree of the first electronic expansion valve and/or the second electronic expansion valve. The invention can realize the accurate distribution of the refrigerant, reduce the energy consumption of the system and improve the economy of the whole vehicle.

Description

A kind of automobile temperature control device and its control method

technical field

The invention relates to the technical field of automobile temperature control, in particular to an automobile temperature control device and a control method thereof.

Background technique

With the increasing popularity of new energy vehicles, the requirements for the cruising range of new energy vehicles are also increasing. However, due to the limitation of the vehicle space, the solution of increasing the battery volume is not very feasible, so increasing the energy density of the power battery has become an effective solution that has been used in the industry to improve the cruising range of new energy vehicles. The increase in the energy density of the power battery is accompanied by problems such as large heat generation and high temperature of the battery, which have adverse effects on the power and life of the battery. The battery cooling system is specially used to cool the battery for the above-mentioned problems. It uses the plate heat exchanger to obtain the cold source in the air conditioning system, and then takes the cold energy of the battery to the outside through the water pump, battery cooling plate, pipeline and other components, so that the battery can be cooled. Work at the optimum temperature.

The liquid convection heat transfer coefficient is high, and the cooling performance is good. Due to the large heat capacity of the system, the heating speed is average; in addition, because the liquid cooling system needs to add cold plates, pipes, water pumps, expansion tanks, valves, battery coolers and other components, the weight The larger the system, the larger the volume. In terms of cost control, the liquid cooling system needs to add more water components, so the cost will increase; in terms of performance, in the liquid cooling system, most of the battery cooling uses a solenoid valve + thermal expansion valve throttling control system, thermal expansion Valves are mechanical parts. In order to achieve optimal performance, thermal expansion valves with different opening degrees need to be matched under different thermal loads, which requires more research and development costs, and has certain limitations in control accuracy.

Since there are many couplings and conflicts in the double distillation system itself, in order to make the whole system reach a more stable state, it is necessary to be more reasonable in the distribution of refrigerant flow.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is to provide a vehicle temperature control device and a control method. The method determines the rotational speed of the compressor and adjusts the first electronic expansion valve by judging the cooling demand on the passenger compartment side and the battery side, and according to the judgment result. And the opening of the second electronic expansion valve, to achieve precise control of the amount of refrigerant.

In order to solve the above technical problems, the present invention provides an automobile temperature control device, including a control unit, a compressor, a condenser, a passenger compartment refrigeration system, a battery cooling system, a first electronic expansion valve, a second electronic expansion valve, a first temperature a sensor and a second temperature sensor, the passenger compartment refrigeration system includes a passenger compartment evaporator, the battery cooling system includes a battery evaporator, wherein,

The compressor, condenser, and passenger compartment evaporator form a first closed circuit, and the compressor, condenser, and battery evaporator form a second closed circuit, and the refrigerant flows in the first closed circuit and/or the second closed circuit. flow in a closed loop;

The first electronic expansion valve is arranged on the pipeline between the refrigerant outlet of the condenser and the refrigerant inlet of the passenger compartment evaporator, and the second electronic expansion valve is arranged between the refrigerant outlet of the condenser and the battery evaporation on the pipeline between the refrigerant inlets of the cooler;

The first temperature sensor is used for measuring the first actual temperature value of the evaporator surface of the passenger compartment, and the second temperature sensor is used for measuring the temperature value of the battery pack;

The control unit is configured to receive the first actual temperature value and the temperature value of the battery pack, and judge whether there is a cooling demand on the passenger compartment side according to the first actual temperature value, and judge the battery side according to the temperature value of the battery pack Whether there is a cooling demand is further used to determine the rotational speed value of the compressor and adjust the opening degree of the first electronic expansion valve and/or the second electronic expansion valve according to the judgment result.

Wherein, the device also includes:

a third temperature sensor for measuring the second actual temperature value of the surface of the battery evaporator;

The control unit is further configured to receive and determine the rotational speed value of the compressor according to the second actual temperature value and adjust the opening degree of the second electronic expansion valve when judging that the battery side has a cooling demand.

Wherein, the device further includes: a first integrated temperature and pressure sensor, a second integrated temperature and pressure sensor,

The first integrated temperature and pressure sensor is used to measure the pressure and temperature of the refrigerant at the outlet of the passenger compartment evaporator, and the second integrated temperature and pressure sensor is used to measure the pressure and temperature of the refrigerant at the outlet of the battery evaporator.

The present invention also provides a control method for the aforementioned automobile temperature control device, comprising the following steps:

S1. Real-time monitoring to obtain the first actual temperature value of the evaporator surface of the passenger compartment, the temperature value of the battery pack, the target temperature value of the evaporator surface of the passenger compartment, and the target temperature value of the battery pack;

S2. Determine whether the passenger compartment has a cooling demand according to the first actual temperature value and the target temperature value of the evaporator surface of the passenger compartment, and determine whether the battery pack has a cooling demand according to the temperature value of the battery pack and the target temperature value of the battery pack Whether there is cooling demand on the side;

S3. Determine the rotational speed value of the compressor and adjust the opening degree of the first electronic expansion valve and/or the second electronic expansion valve according to the judgment result of the step S2.

Wherein, the step S2 specifically includes:

Calculate the first difference between the first actual temperature value of the evaporator surface of the passenger compartment and the target temperature value of the evaporator surface of the passenger compartment, and if the first difference is greater than the first set value, determine The passenger compartment side has a cooling demand, otherwise the passenger compartment side does not have a cooling demand;

Calculate the second difference between the battery pack temperature value and the battery pack target temperature value. If the second difference is greater than the second set value, it is determined that the battery side has a cooling demand, otherwise the battery side There is no cooling requirement.

Wherein, the step S3 specifically includes:

If only the side of the passenger compartment has a cooling demand, the second electronic expansion valve is closed and the first strategy is executed, and the first strategy is specifically:

Obtaining the actual temperature value and the target temperature value in the vehicle, and determining the rotational speed value of the compressor according to the actual temperature value and the target temperature value in the vehicle;

The current first difference value is calculated, and the opening degree of the first electronic expansion valve is adjusted according to the current first difference value.

Wherein, the step S3 specifically further includes:

If only the battery side has cooling demand, the first electronic expansion valve is closed and the second strategy is executed, and the second strategy is specifically:

Obtain the second actual temperature value of the surface of the battery evaporator and the target temperature of the surface of the battery evaporator, and calculate the third actual temperature value between the second actual temperature value of the surface of the battery evaporator and the target temperature of the surface of the battery evaporator difference;

The rotational speed value of the compressor is determined according to the third difference value, and the opening degree of the second electronic expansion valve is adjusted according to the third difference value.

Wherein, the step S3 specifically further includes:

When both the passenger compartment side and the battery side have cooling demands, the cooling priorities of the passenger compartment side and the battery side are further judged, and based on the cooling priorities of the passenger compartment side and the battery side The rotational speed value of the compressor is determined and the opening degree of the first electronic expansion valve and/or the second electronic expansion valve is adjusted.

Wherein, determining the rotational speed value of the compressor and adjusting the opening degree of the first electronic expansion valve and/or the second electronic expansion valve according to the cooling priority of the passenger compartment side and the battery side include:

If the battery-side cooling priority is a high priority, the first electronic expansion valve is closed and a second strategy is executed, wherein the second strategy is: acquiring a second actual temperature value on the surface of the battery evaporator and the target temperature of the surface of the battery evaporator, calculating a third difference between the second actual temperature value of the surface of the battery evaporator and the target temperature of the surface of the battery evaporator, and determining the compressor according to the third difference and adjust the opening of the second electronic expansion valve according to the third difference;

If only the refrigeration priority on the passenger compartment side is a high priority, the second electronic expansion valve is closed and a first strategy is executed, wherein the first strategy is: obtaining the actual temperature value in the vehicle and the target temperature value, and determine the rotational speed value of the compressor according to the actual temperature value in the vehicle and the target temperature value, calculate the current first difference value, and adjust the first difference value according to the current first difference value. The opening of the electronic expansion valve;

If the cooling priorities of the passenger compartment side and the battery side are both low priorities, the passenger compartment refrigeration system executes the first strategy, the battery cooling system executes the second strategy, and the compression The total rotational speed value of the compressor is the sum of the rotational speed value of the compressor obtained by the first strategy and the rotational speed value of the compressor obtained by the second strategy.

Wherein, determining the rotational speed value of the compressor according to the actual temperature value and the target temperature value in the vehicle specifically includes:

Determine whether the actual temperature value in the car is less than the target temperature value in the car, if so, make the rotational speed value of the compressor zero; otherwise, further calculate the current first difference, and according to the current first difference The difference obtains the rotational speed value of the compressor.

Wherein, the following formula is used to calculate the rotational speed value of the compressor through the current first difference:

Compressor speed value=k ₁ ΔT1+k ₂

Wherein, ΔT1 is the current first difference value, and k ₁ and k ₂ are the set first and second coefficient values, respectively.

Wherein, the obtaining the rotational speed value of the compressor according to the current first difference further includes:

When the rotational speed value of the compressor calculated according to the current first difference value is greater than zero, the current superheat degree of the refrigerant at the exit of the evaporator of the passenger compartment is further calculated. The third set value and the current superheat degree of the refrigerant at the exit of the passenger compartment evaporator is less than the fourth set value, so that the rotational speed value of the compressor is zero.

Wherein, the adjusting the opening degree of the first electronic expansion valve according to the current first difference specifically includes:

Determine whether the current first difference is greater than zero, and if the current first difference is greater than zero, further obtain the target value of the superheat of the refrigerant at the exit of the evaporator of the passenger compartment and calculate the current overheating of the refrigerant at the exit of the evaporator of the passenger compartment. and determine whether the current superheat degree of the refrigerant at the outlet of the evaporator of the passenger compartment is greater than the target value of the superheat degree of the refrigerant at the outlet of the passenger compartment. decrease in opening;

If the current first difference is less than zero, the first electronic expansion valve is closed.

Wherein, the determining the rotational speed value of the compressor according to the third difference specifically includes:

The rotational speed value of the compressor is obtained by calculating the third difference value. When the rotational speed value of the compressor obtained by calculation is greater than zero, the current superheat degree of the refrigerant at the outlet of the battery evaporator is further obtained by calculation. When the second actual temperature value is less than the fifth set value and the current superheat degree of the refrigerant at the outlet of the battery evaporator is less than the sixth set value, the rotational speed value of the compressor is set to zero.

Wherein, the obtaining the rotational speed value of the compressor by calculating the third difference specifically includes:

Compressor speed value=k ₃ ΔT2+k ₄

Among them, ΔT2 is the third difference value, and k ₃ and k ₄ are the set third and fourth coefficients, respectively.

Wherein, the adjusting the opening degree of the second electronic expansion valve according to the third difference specifically includes:

Determine whether the third difference is less than zero, and if so, close the second electronic expansion valve, otherwise, further obtain the target value of the superheat of the refrigerant at the outlet of the battery evaporator and calculate the current value of the superheat of the refrigerant at the outlet of the battery evaporator, And judge whether the current superheat value of the refrigerant at the outlet of the battery evaporator is greater than the target value of the superheat of the refrigerant at the outlet of the battery evaporator, if so, increase the opening of the second electronic expansion valve, otherwise make the second electronic expansion valve. The opening of the expansion valve decreases.

The beneficial effect of the embodiment of the present invention is that: by considering the cooling demand on the battery side and the passenger compartment side, and calculating the rotational speed of the compressor, the opening of the first electronic expansion valve and the second electronic expansion valve according to the specific cooling demand, and when When both the passenger compartment side and the battery side have cooling demands, the rotational speed of the compressor and the opening degrees of the first electronic expansion valve and the second electronic expansion valve are determined according to the cooling priority. The temperature control method of the present invention cools the power battery under high temperature conditions, so that the power battery can quickly reach a suitable working temperature, change the charging and discharging performance of the power battery in a high temperature environment, improve the power performance of the whole vehicle under high temperature, and at the same time It can prevent the battery from working at high temperature for a long time, protect the power battery, and effectively prolong the life of the power battery; in addition, the present invention also considers the user's comfort during the use of the vehicle, and also considers the performance of the battery pack. Safety features, so that the entire system is always in an optimal state. Finally, the characteristics of the electronic expansion valve are fully utilized in the refrigerant flow distribution of the present invention, which can control the refrigerant flow in the system more accurately, and further reduce the energy consumption of the system. Improve the economy of the vehicle.

Description of drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained according to these drawings without creative efforts.

FIG. 1 is a schematic structural diagram of an automobile temperature control device according to an embodiment of the present invention.

FIG. 2 is a schematic diagram of the connection relationship of some components of an automobile temperature control device according to an embodiment of the present invention.

FIG. 3 is a schematic flowchart of a control method for an automobile temperature control device according to an embodiment of the present invention.

Detailed ways

The following descriptions of the various embodiments refer to the accompanying drawings to illustrate specific embodiments in which the invention may be practiced.

1-2, the first embodiment of the present invention provides an automobile temperature control device, the control device includes a control unit 15, a compressor 1, a condenser 2, a passenger compartment refrigeration system, a battery cooling system, a first electronic The expansion valve 4, the second electronic expansion valve 8, the first temperature sensor 5 and the second temperature sensor 14, the passenger compartment refrigeration system includes the passenger compartment evaporator 6, the battery cooling system includes the battery evaporator 10, wherein,

The compressor 1, the condenser 2, and the passenger compartment evaporator 6 form a first closed circuit, and the compressor 1, the condenser 2, and the battery evaporator 10 form a second closed circuit. The refrigerant flows between the first closed circuit and the battery evaporator. /or flow in the second closed circuit; the first electronic expansion valve 4 is arranged on the pipeline between the refrigerant outlet of the condenser 2 and the refrigerant inlet of the passenger compartment evaporator 6, and the second electronic expansion valve 8 It is arranged on the pipeline between the refrigerant outlet of the condenser 2 and the refrigerant inlet of the battery evaporator 10; the first temperature sensor 5 is used to measure the first actual temperature value of the surface of the evaporator 6 in the passenger compartment, so The second temperature sensor 14 is used to measure the temperature value of the battery pack 13; the control unit 15 is used to receive the first actual temperature value and the battery pack temperature value, and determine the passenger compartment according to the first actual temperature value Whether there is a cooling demand on the side and whether there is a cooling demand on the battery side according to the temperature value of the battery pack, it is further used to determine the rotational speed value of the compressor and adjust the first electronic expansion valve 4 and/or the The opening degree of the second electronic expansion valve 8 .

In a specific embodiment, the device further includes a third temperature sensor 9 for measuring the second actual temperature value of the surface of the battery evaporator 10 .

In a specific embodiment, the control device further comprises a first integrated temperature and pressure sensor 7 arranged on the pipeline of the refrigerant outlet of the evaporator of the passenger compartment, which is used to measure the temperature and pressure of the refrigerant at the outlet of the evaporator 6 of the passenger compartment, and The second integrated temperature and pressure sensor 11 arranged on the pipeline of the refrigerant outlet of the battery evaporator is used to measure the temperature and pressure of the refrigerant at the outlet of the battery evaporator 10 .

In a specific embodiment, the device further includes a high-pressure pressure sensor 3 disposed at the refrigerant outlet of the condenser 2 , and the high-pressure pressure sensor 3 is used to measure the pressure value of the refrigerant at the outlet of the condenser 2 .

In a specific embodiment, the control device further includes a gas-liquid separator 12. In order to prevent some liquid refrigerants from entering the compressor 1 without being completely evaporated, the gas-liquid separator 12 is provided to separate gas and liquid, so that the gas is not completely evaporated. The gaseous liquid refrigerant is filtered, and only the low-temperature and low-pressure gaseous refrigerant is allowed to flow back to the compressor 1 through the pipeline to prevent liquid shock to the compressor.

Based on the first embodiment of the present invention, the second embodiment of the present invention provides a control method for the aforementioned automobile temperature control device. As shown in FIG. 3 , the method includes the following steps:

S1. Real-time monitoring to obtain the first actual temperature value of the evaporator surface of the passenger compartment, the temperature value of the battery pack, the target temperature value of the evaporator surface of the passenger compartment, and the target temperature value of the battery pack.

Specifically, the target temperature value of the battery pack is specifically determined according to the performance of the battery pack.

S2. Determine whether there is a cooling demand on the side of the passenger compartment according to the first actual temperature value and the target temperature value of the evaporator surface of the passenger compartment, and determine whether the battery pack is required according to the temperature value of the battery pack and the target temperature value of the battery pack Whether there is cooling demand on the side.

Wherein, the method for judging whether there is a cooling demand on the side of the passenger compartment is: calculating the first difference between the first actual temperature value of the evaporator surface of the passenger compartment and the target temperature value of the evaporator surface of the passenger compartment, if the If the first difference is greater than the first set value, it is determined that there is a cooling demand on the passenger compartment side, otherwise there is no cooling demand on the passenger compartment side.

Specifically, the first set value may be 3 degrees Celsius, and when the first difference is greater than 3 degrees Celsius, it means that there is a cooling demand on the side of the passenger compartment, otherwise there is no cooling demand.

The method for judging whether the battery side has cooling demand is: calculating a second difference between the battery pack temperature value and the battery pack target temperature value, and when the second difference value is greater than the second set value, the battery pack There is a cooling demand on the side, otherwise there is no cooling demand.

The target temperature value of the battery pack is determined according to the performance of the battery pack, and the second set value is 0. That is, when the actual temperature value of the battery pack is greater than the target temperature value of the battery pack, there is a cooling demand on the battery side, otherwise there is no cooling demand.

In practical applications, the possible situations that require cooling in step S2 are: 1. Only the passenger compartment has a cooling demand; 2. Only the battery side has a cooling demand; 3. Both the passenger compartment and the battery side have a cooling demand.

S3. Determine the rotational speed value of the compressor and adjust the opening degree of the first electronic expansion valve and/or the second electronic expansion valve according to the judgment result of the step S2.

According to the judgment result of step S2, when only the passenger compartment has a cooling demand, the second electronic expansion valve is closed and the first strategy is executed. The first strategy is specifically: obtaining the actual temperature value in the vehicle and the target temperature value, and determine the rotational speed value of the compressor according to the actual temperature value in the vehicle and the target temperature value; calculate the first difference value in real time, and adjust the first electronic expansion valve according to the first difference value of opening.

Wherein, calculating and obtaining the rotational speed value of the compressor according to the actual temperature value and the target temperature value in the vehicle specifically includes: judging whether the actual temperature value in the vehicle is less than the target temperature value in the vehicle, and if so, making the rotational speed value of the compressor is zero; otherwise, the current first difference value is further calculated, and the rotational speed value of the electric compressor is obtained according to the current first difference value.

Specifically, the following formula is used to obtain the rotational speed value of the compressor through the current first difference calculation:

Compressor speed value=k ₁ ΔT1+k ₂

Wherein, ΔT1 is the current first difference value, and k ₁ and k ₂ are the set first and second coefficient values, respectively.

After the rotational speed value of the compressor is obtained by calculating the current first difference value, in order to take into account the temperature protection and overheating protection of the passenger compartment, obtaining the rotational speed value of the electric compressor according to the current first difference value also includes: If the rotational speed value of the compressor obtained by the first difference calculation is greater than zero, the current superheat degree of the refrigerant at the evaporator outlet of the passenger compartment is further calculated. If the current superheat degree of the refrigerant at the outlet of the passenger compartment evaporator is less than the fourth set value, the rotational speed value of the compressor is set to zero.

Specifically, the method for calculating the superheat degree of the refrigerant at the outlet of the passenger compartment evaporator is as follows: obtaining the temperature value and pressure value of the refrigerant at the outlet of the passenger compartment evaporator measured by the first integrated temperature and pressure sensor, and calculating and obtaining the passenger compartment according to the pressure value of the refrigerant at the outlet of the passenger compartment. For the saturation temperature of the refrigerant at the outlet of the cabin evaporator, since the refrigerant is R134A, the calculation method of the saturated temperature of the refrigerant at the outlet of the evaporator in the passenger compartment can refer to the R134A refrigerant saturation temperature pressure gauge. The superheat degree of the refrigerant at the exit of the passenger compartment evaporator is equal to the value of the refrigerant temperature at the exit of the passenger compartment evaporator minus the saturated temperature of the refrigerant at the exit of the passenger compartment evaporator.

The third set value may be 0, and the fourth set value may be 3, that is, in the case where the calculated rotational speed value of the compressor is greater than 0, if the temperature value of the evaporator surface of the passenger compartment is less than 0 degrees, and the passenger When the superheat degree of the refrigerant at the outlet of the cabin evaporator is less than 3, the rotational speed of the compressor is set to 0.

Specifically, adjusting the opening value of the first electronic expansion valve according to the first difference value specifically includes: judging whether the current first difference value is greater than zero, that is, judging the current first actual temperature of the evaporator surface of the passenger compartment Whether the value is greater than the target temperature value of the evaporator surface of the passenger compartment, if the current first difference is greater than zero, then further obtain the target value of the superheat of the refrigerant at the outlet of the evaporator of the passenger compartment and calculate the current superheat of the refrigerant at the outlet of the evaporator of the passenger compartment, And judge whether the current superheat degree of the refrigerant at the outlet of the evaporator of the passenger compartment is greater than the target value of the superheat degree of the refrigerant at the outlet of the passenger compartment. decrease; if the current first difference is less than zero, the first electronic expansion valve is closed.

According to the judgment result of step S2, when only the battery side has cooling demand, the first electronic expansion valve is closed and the second strategy is executed. temperature and the target temperature of the surface of the battery evaporator, calculating a third difference between the second actual temperature of the surface of the battery evaporator and the target temperature of the surface of the battery evaporator; and determining to obtain the compression according to the third difference The rotational speed value of the engine is adjusted and the opening degree of the second electronic expansion valve is adjusted according to the third difference value.

Wherein, the calculating and obtaining the rotational speed value of the compressor according to the third difference value specifically includes: calculating and obtaining the rotational speed value of the compressor by using the third difference value, and when the rotational speed value of the compressor obtained by calculation is greater than zero, then Further calculate and obtain the current superheat degree of the refrigerant at the outlet of the battery evaporator, when the actual temperature value of the surface of the battery evaporator is less than the fifth set value and the current superheat degree of the refrigerant outlet of the battery evaporator is less than the sixth set value, so that all The speed value of the compressor is zero.

Specifically, the rotational speed value of the compressor obtained by calculating the third difference is as follows:

Compressor speed value=k ₃ ΔT2+k ₄

Among them, ΔT2 is the third difference value, and k ₃ and k ₄ are the third and fourth coefficients, respectively, which are both constants.

Specifically, the fifth set value may be 5 degrees Celsius, and the sixth set value may be 3.

Among them, the calculation method of the superheat degree of the refrigerant at the outlet of the battery evaporator is: obtain the current temperature and pressure value of the refrigerant at the outlet of the battery evaporator measured by the second integrated temperature and pressure sensor, and use the pressure value of the refrigerant at the outlet of the battery evaporator to calculate and obtain the outlet of the battery evaporator. The saturation temperature value of the refrigerant and the calculation method of the saturation temperature value of the refrigerant at the outlet of the battery evaporator can also refer to the R134A refrigerant saturation temperature pressure gauge. The current superheat degree of the refrigerant at the outlet of the battery evaporator is equal to the current temperature value of the refrigerant at the outlet of the battery evaporator minus The saturation temperature value of the refrigerant at the outlet of the battery evaporator.

The adjusting the opening degree of the second electronic expansion valve according to the third difference specifically includes: judging whether the third difference is less than zero, and if so, closing the second electronic expansion valve, otherwise Further obtain the target value of the superheat degree of the refrigerant outlet of the battery evaporator and calculate the current superheat value of the refrigerant outlet of the battery evaporator, and judge whether the current superheat value of the refrigerant outlet of the battery evaporator is greater than the superheat of the refrigerant outlet of the battery evaporator. If the heat target value is yes, the opening degree of the second electronic expansion valve is increased, otherwise, the opening degree of the second electronic expansion valve is decreased.

According to the judgment result of step S2, when both the battery side and the passenger cabin side need to be cooled at the same time, the cooling priority of the battery side and the passenger cabin side is further judged, and the cooling priority of the battery side and the passenger cabin side is determined according to the cooling priority of the electric compressor. The rotational speed value and the opening degree of the first electronic expansion valve and/or the second electronic expansion valve.

Specifically, the method for determining the cooling priority of the passenger compartment is as follows: the cooling priority of the passenger compartment is divided into three levels in total, namely the lowest priority, the low priority and the high priority; when there is no cooling demand on the passenger compartment, At this time, the lowest priority is the lowest priority. When there is a cooling demand on the side of the passenger compartment, the current refrigeration priority is determined according to the first actual temperature value of the evaporator surface of the passenger compartment. The lower the first temperature of the evaporator surface of the passenger compartment is. , the lower the cooling priority on the passenger compartment side, the higher the first actual temperature value of the evaporator surface in the passenger compartment, and the higher the cooling priority on the passenger compartment side, The cooling priority of the side is classified into the corresponding low priority or high priority.

Specifically, the method for determining the cooling priority of the battery side is as follows: the cooling priority of the battery side is divided into three levels in total, namely the lowest priority, the low priority and the high priority; when the battery side has no cooling demand, the battery side The priority of cooling is the lowest, which is the lowest priority. When there is a cooling demand on the battery side, it is determined according to the battery temperature and the second actual temperature of the surface of the battery evaporator. The higher the battery temperature is, the higher the priority of cooling on the battery side is, and the lower the battery temperature is, the lower the priority of cooling on the battery side is. After judging the battery temperature, it is preliminarily determined that the priority of cooling on the battery side is high, and then it is further judged that the battery has evaporated. The second actual temperature value on the surface of the evaporator, at this time, if the second actual temperature value on the surface of the battery evaporator is low, the battery side cooling priority is a low priority.

When the cooling priority on the battery side is high, regardless of whether the priority on the passenger compartment side is high, the first electronic expansion valve is closed and the second strategy is executed to ensure that the battery side is given priority for cooling.

When only the refrigeration priority on the passenger compartment side is high priority, that is, the refrigeration priority on the passenger compartment side is high priority and the refrigeration priority on the battery side is not high priority, close the second electronic expansion valve and execute the first The strategy is to give priority to the cooling of the passenger compartment at this time.

When the cooling priorities on the passenger compartment side and the battery side are both low priorities, the passenger compartment refrigeration system executes the first strategy for cooling, and the battery cooling system executes the second refrigeration strategy for cooling.

It should be noted that, in the case where the cooling priority of the passenger compartment side and the battery side is low priority, the passenger compartment refrigeration system executes the first strategy to obtain a rotational speed value of an electric compressor, and the battery cooling system executes the second strategy. An electric compressor rotational speed value can be obtained by calculation. At this time, the total rotational speed of the electric compressor is the sum of the rotational speed value of the electric compressor obtained by executing the first strategy calculation and the rotational speed value of the electric compressor obtained by executing the second strategy calculation.

When the cooling priority on the passenger compartment side and the battery side is low priority, the temperature protection and overheating protection on the passenger compartment side and the temperature protection and overheating protection on the battery side need to be considered in the same way. Specifically, when the calculated total rotational speed value of the compressor is greater than zero, if the first actual temperature value of the passenger compartment evaporator is less than the third set value, the current superheat degree of the refrigerant at the exit of the passenger compartment evaporator is less than the fourth Set value, when the second temperature value on the surface of the battery evaporator is less than the fifth set value and the superheat of the refrigerant at the outlet of the battery evaporator is less than the sixth set value, the total rotational speed of the electric compressor is made zero.

The temperature control method of the embodiment of the present invention calculates the rotational speed of the compressor, the opening degrees of the first electronic expansion valve and the second electronic expansion valve by considering the cooling demand of the battery side and the passenger compartment side, and calculates the rotation speed of the compressor according to the specific cooling demand. When both the passenger compartment side and the battery side have cooling demands, the rotational speed of the electric compressor and the opening degrees of the first electronic expansion valve and the second electronic expansion valve are determined according to the cooling priority. The temperature control method of the present invention cools the power battery under high temperature conditions, so that the power battery can quickly reach a suitable working temperature, change the charging and discharging performance of the power battery in a high temperature environment, improve the power performance of the whole vehicle under high temperature, and at the same time It can prevent the battery from working at high temperature for a long time, protect the power battery, and effectively prolong the life of the power battery; in addition, the present invention also considers the user's comfort during the use of the vehicle, and also considers the performance of the battery pack. Safety features, so that the entire system is always in an optimal state. Finally, the characteristics of the electronic expansion valve are fully utilized in the refrigerant flow distribution of the present invention, which can control the refrigerant flow in the system more accurately, and further reduce the energy consumption of the system. Improve the economy of the vehicle.

The above disclosures are only preferred embodiments of the present invention, and of course, the scope of the rights of the present invention cannot be limited by this. Therefore, equivalent changes made according to the claims of the present invention are still within the scope of the present invention.

Claims (16)

1. An automotive temperature control arrangement, characterized by comprising a control unit, a compressor, a condenser, a passenger compartment refrigeration system, a battery cooling system, a first electronic expansion valve, a second electronic expansion valve, a first temperature sensor and a second temperature sensor, the passenger compartment refrigeration system comprising a passenger compartment evaporator, the battery cooling system comprising a battery evaporator, wherein,

the compressor, the condenser and the passenger compartment evaporator form a first closed loop, the compressor, the condenser and the battery evaporator form a second closed loop, and a refrigerant flows in the first closed loop and/or the second closed loop;

the first electronic expansion valve is arranged on a pipeline between the refrigerant outlet of the condenser and the refrigerant inlet of the passenger compartment evaporator, and the second electronic expansion valve is arranged on a pipeline between the refrigerant outlet of the condenser and the refrigerant inlet of the battery evaporator;

the first temperature sensor is used for measuring a first actual temperature value of the surface of the passenger compartment evaporator, and the second temperature sensor is used for measuring a battery pack temperature value;

the control unit is used for receiving the first actual temperature value and the battery pack temperature value, judging whether the passenger compartment side has a refrigeration demand according to the first actual temperature value and judging whether the battery side has the refrigeration demand according to the battery pack temperature value, and further used for determining the rotating speed value of the compressor according to the judgment result and adjusting the opening degree of the first electronic expansion valve and/or the second electronic expansion valve.

2. The apparatus of claim 1, further comprising:

a third temperature sensor for measuring a second actual temperature value of the battery evaporator surface;

and the control unit is also used for receiving and determining the rotating speed value of the compressor according to the second actual temperature value and adjusting the opening degree of the second electronic expansion valve when the battery side is judged to have a refrigeration demand.

3. The apparatus of claim 2, further comprising: a first temperature and pressure integrated sensor, a second temperature and pressure integrated sensor,

the first temperature and pressure integrated sensor is used for measuring the pressure and the temperature of a refrigerant at the outlet of the evaporator of the passenger compartment, and the second temperature and pressure integrated sensor is used for measuring the pressure and the temperature of a refrigerant at the outlet of the battery evaporator.

4. A control method for the automotive temperature control apparatus according to any one of claims 1 to 3, characterized by comprising the steps of:

s1, monitoring and acquiring a first actual temperature value of the surface of the passenger compartment evaporator, a battery pack temperature value, a target temperature value of the surface of the passenger compartment evaporator and a target temperature value of the battery pack in real time;

s2, judging whether the passenger compartment side has a refrigeration demand according to the first actual temperature value and the target temperature value of the passenger compartment evaporator surface and judging whether the battery side has the refrigeration demand according to the battery pack temperature value and the battery pack target temperature value;

s3, determining the rotation speed value of the compressor according to the judgment result of the step S2 and adjusting the opening degree of the first electronic expansion valve and/or the second electronic expansion valve.

5. The method according to claim 4, wherein the step S2 specifically includes:

calculating a first difference value between a first actual temperature value on the surface of the passenger compartment evaporator and a target temperature value on the surface of the passenger compartment evaporator, if the first difference value is greater than a first set value, judging that the passenger compartment side has a refrigeration demand, otherwise, judging that the passenger compartment side does not have the refrigeration demand;

and calculating a second difference value between the battery pack temperature value and the battery pack target temperature value, if the second difference value is greater than a second set value, judging that the battery side has a refrigeration requirement, otherwise, judging that the battery side does not have the refrigeration requirement.

6. The method according to claim 5, wherein the step S3 specifically includes:

if only the passenger compartment side has a refrigeration demand, closing the second electronic expansion valve and executing a first strategy, wherein the first strategy specifically comprises the following steps:

acquiring an actual temperature value and a target temperature value in the automobile, and determining a rotating speed value of a compressor according to the actual temperature value and the target temperature value in the automobile;

and calculating the current first difference, and adjusting the opening degree of the first electronic expansion valve according to the current first difference.

7. The method according to claim 5, wherein the step S3 specifically includes:

if only the battery side has a refrigeration demand, closing the first electronic expansion valve and executing a second strategy, wherein the second strategy specifically comprises the following steps:

acquiring a second actual temperature value of the surface of the battery evaporator and a target temperature value of the surface of the battery evaporator, and calculating a third difference value between the second actual temperature value of the surface of the battery evaporator and the target temperature value of the surface of the battery evaporator;

and determining the rotating speed value of the compressor according to the third difference value and adjusting the opening degree of the second electronic expansion valve according to the third difference value.

8. The method of claim 5, wherein: the step S3 specifically includes:

when the passenger compartment side and the battery side have refrigeration requirements, the refrigeration priorities of the passenger compartment side and the battery side are further judged, the rotating speed value of the compressor is determined according to the refrigeration priorities of the passenger compartment side and the battery side, and the opening degree of the first electronic expansion valve and/or the second electronic expansion valve is/are adjusted.

9. The method of claim 8, wherein: the determining the rotation speed value of the compressor and adjusting the opening degree of the first electronic expansion valve and/or the second electronic expansion valve according to the refrigeration priorities of the passenger compartment side and the battery side specifically includes:

if the battery side refrigeration priority is a high priority, closing the first electronic expansion valve and executing a second strategy, wherein the second strategy is as follows: acquiring a second actual temperature value of the surface of the battery evaporator and a target temperature of the surface of the battery evaporator, calculating a third difference value between the second actual temperature value of the surface of the battery evaporator and the target temperature of the surface of the battery evaporator, determining a rotating speed value of a compressor according to the third difference value, and adjusting the opening degree of the second electronic expansion valve according to the third difference value;

if only the refrigeration priority of the passenger compartment side is high priority, closing the second electronic expansion valve and executing a first strategy, wherein the first strategy is as follows: acquiring the actual temperature value and the target temperature value in the automobile, determining the rotating speed value of a compressor according to the actual temperature value and the target temperature value in the automobile, calculating the current first difference value, and adjusting the opening degree of the first electronic expansion valve according to the current first difference value;

and if the refrigeration priorities of the passenger compartment side and the battery side are both low priorities, the passenger compartment refrigeration system executes the first strategy, the battery cooling system executes the second strategy, and the total rotating speed value of the compressor at the moment is the sum of the rotating speed value of the compressor obtained by the first strategy and the rotating speed value of the compressor obtained by the second strategy.

10. The method according to claim 6 or 9, characterized in that: the step of determining the rotating speed value of the compressor according to the actual temperature value and the target temperature value in the automobile specifically comprises the following steps:

judging whether the actual temperature value in the automobile is smaller than the target temperature value in the automobile, and if so, enabling the rotating speed value of the compressor to be zero; otherwise, further calculating the current first difference value, and obtaining the rotating speed value of the compressor according to the current first difference value.

11. The method of claim 10, wherein: calculating the rotation speed value of the compressor by using the current first difference value according to the following formula:

speed value k of compressor₁ΔT1+k₂

Where Δ T1 is the current first difference value, k₁And k₂Respectively, a first coefficient value and a second coefficient value.

12. The method according to claim 11, wherein the obtaining the rotation speed value of the compressor according to the current first difference further comprises:

and when the rotating speed value of the compressor obtained by calculation according to the current first difference value is larger than zero, further calculating the current superheat degree of the refrigerant at the outlet of the passenger compartment evaporator, and if the first actual temperature value of the surface of the passenger compartment evaporator is smaller than a third set value and the current superheat degree of the refrigerant at the outlet of the passenger compartment evaporator is smaller than a fourth set value, enabling the rotating speed value of the compressor to be zero.

13. The method according to claim 6 or 9, wherein the adjusting the opening degree of the first electronic expansion valve according to the current first difference specifically comprises:

judging whether the current first difference is larger than zero, if so, further obtaining a target value of the superheat degree of the refrigerant at the outlet of the passenger compartment evaporator and calculating the current superheat degree of the refrigerant at the outlet of the passenger compartment evaporator, judging whether the current superheat degree of the refrigerant at the outlet of the passenger compartment evaporator is larger than the target value of the superheat degree of the refrigerant at the outlet of the passenger compartment, if so, increasing the opening degree of the first electronic expansion valve, otherwise, reducing the opening degree of the first electronic expansion valve;

and if the current first difference value is smaller than zero, closing the first electronic expansion valve.

14. The method according to claim 7 or 9, wherein said determining a rotation speed value of the compressor from said third difference value comprises in particular:

and calculating to obtain a rotating speed value of the compressor through the third difference, further calculating to obtain the current superheat degree of the refrigerant at the outlet of the battery evaporator when the rotating speed value of the compressor obtained through calculation is larger than zero, and enabling the rotating speed value of the compressor to be zero when the second actual temperature value on the surface of the battery evaporator is smaller than a fifth set value and the current superheat degree of the refrigerant at the outlet of the battery evaporator is smaller than a sixth set value.

15. The method according to claim 14, wherein said obtaining of the rotation speed value of the compressor by said third difference calculation comprises in particular:

speed value k of compressor₃ΔT2+k₄

Where Δ T2 is the third difference, k₃、k₄Respectively, the set third coefficient and the set fourth coefficient.

16. The method of claim 15, wherein the adjusting the opening degree of the second electronic expansion valve according to the third difference specifically comprises:

and judging whether the third difference is smaller than zero, if so, closing the second electronic expansion valve, otherwise, further obtaining a target value of the superheat degree of the refrigerant at the outlet of the battery evaporator and calculating the current superheat degree value of the refrigerant at the outlet of the battery evaporator, and judging whether the current superheat degree value of the refrigerant at the outlet of the battery evaporator is larger than the target value of the superheat degree of the refrigerant at the outlet of the battery evaporator, if so, increasing the opening degree of the second electronic expansion valve, otherwise, reducing the opening degree of the second electronic expansion valve.

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